論文 - 武田 彩希
-
Takeda A., Mori K., Nishioka Y., Hida T., Yukumoto M., Kanemaru Y., Yonemura S., Mieda K., Tsuru T.G., Tanaka T., Kurachi I., Arai Y.
Journal of Instrumentation 15 ( 12 ) 2020年12月
担当区分:筆頭著者 記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
This paper reports on the development of on-chip pattern processing in the event-driven silicon-on-insulator pixel detector for X-ray astronomy with background rejection purpose. X-ray charge-coupled device (CCD) detectors, well-established pixel detectors used in this field, has proven that classification of detected events considering their spatial pattern is effective for particle background rejection. Based on the current architecture of our device and from the CCD images obtained in space, we first established a design concept and algorithm of the pattern processor to be implemented. Then, we developed a new device, including a prototype pattern-processing circuit. Experiments using X-ray and beta-ray radioisotopes demonstrated that the pattern processor properly works as expected, and the particle background rejection is realized in an on-chip fashion. This function is useful, especially in a limited-resource system such as the CubeSat.
-
Takeda A., Mori K., Nishioka Y., Fukuda K., Yukumoto M., Hida T., Tsuru T.G., Tanaka T., Uchida H., Hayashi H., Harada S., Okuno T., Kayama K., Arai Y., Kurachi I., Kohmura T., Hagino K., Negishi K., Oono K., Yarita K., Matsumura H., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H.
Journal of Instrumentation 15 ( 11 ) 2020年11月
担当区分:筆頭著者 記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
This paper reports the spectroscopic performance improvement of the silicon-oninsulator (SOI) pixel detector for X-ray astronomy, by introducing a double-SOI (D-SOI) structure. For applications inX-ray astronomical observatories, we have been developing a series of monolithic active pixel sensors, named as “XRPIXs,” based on SOI pixel technology. The D-SOI structure has an advantage that it can suppress a parasitic capacitance between the sensing node and the circuit layer, due to which the closed-loop gain cannot be increased in our conventional XRPIXs with a single-SOI (S-SOI) structure. Compared to the S-SOI XRPIX, the closed-loop gain is doubled in the D-SOI XRPIX. The readout noise is effectively lowered to 33% (16 e (rms)), and the energy resolution at 6.4 keV is improved by a factor of 1.7 (290 eV in FWHM). The suppression of the parasitic capacitance is also quantitatively evaluated based on the results of capacitance extraction simulation from the layout. This evaluation provides design guidelines for further reduction of the readout noise.
-
Single event tolerance of x-ray silicon-on-insulator pixel sensors 査読あり
Hagino K., Hayashida M., Kohmura T., Doi T., Tsunomachi S., Kitajima M., Tsuru T.G., Uchida H., Kayama K., Mori K., Takeda A., Nishioka Y., Yukumoto M., Mieda K., Yonemura S., Ishida T., Tanaka T., Arai Y., Kurachi I., Kitamura H., Kawahito S., Yasutomi K.
Journal of Astronomical Telescopes, Instruments, and Systems 8 ( 4 ) 2022年10月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Astronomical Telescopes, Instruments, and Systems
We evaluate the single event tolerance of the x-ray silicon-on-insulator (SOI) pixel sensor named XRPIX, developed for the future x-ray astronomical satellite FORCE. In this work, we measure the cross-section of single event upset (SEU) of the shift register on XRPIX by irradiating heavy ion beams with linear energy transfer (LET) ranging from 0.022 to 68 MeV / (mg/cm2). From the SEU cross-section curve, the saturation cross-section and threshold LET are successfully obtained to be 3.4-0.9+2.9×10-10 cm2/bit and 7.3-3.5+1.9 MeV/(mg/cm2), respectively. Using these values, the SEU rate in orbit is estimated to be â‰2 0.1 event / year primarily due to the secondary particles induced by cosmic-ray protons. This SEU rate of the shift register on XRPIX is negligible in the FORCE orbit.
-
A broadband X-ray imaging spectroscopy in the 2030s: the FORCE mission 査読あり 国際共著
Koji MORI, Ayaki TAKEDA
Proceedings of SPIE - The International Society for Optical Engineering 121812 1218122 2022年7月
記述言語:英語 掲載種別:研究論文(国際会議プロシーディングス)
DOI: 10.1117/12.2628772
-
Kitajima M., Hagino K., Kohmura T., Hayashida M., Oono K., Negishi K., Yarita K., Doi T., Tsunomachi S., Tsuru T.G., Uchida H., Kayama K., Kodama R., Tanaka T., Mori K., Takeda A., Nishioka Y., Yukumoto M., Mieda K., Yonemura S., Ishida T., Arai Y., Kurachi I.
Journal of Astronomical Telescopes, Instruments, and Systems 8 ( 2 ) 2022年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Astronomical Telescopes, Instruments, and Systems
We have been developing the monolithic active pixel detector XRPIX onboard the future x-ray astronomical satellite FORCE. XRPIX is composed of complementary metal-oxide-semiconductor pixel circuits, SiO2 insulator, and Si sensor by utilizing the silicon-on-insulator (SOI) technology. When the semiconductor detector is operated in orbit, it suffers from radiation damage due to x-rays emitted from celestial objects as well as cosmic rays. From previous studies, positive charges trapped in the SiO2 insulator are known to cause degradation of the detector performance. To improve the radiation hardness, we developed XRPIX equipped with a double-SOI (D-SOI) structure, introducing an additional silicon layer in the SiO2 insulator. This structure is aimed at compensating for the effect of the trapped positive charges. Although the radiation hardness of the D-SOI detectors to cosmic rays has been evaluated, the radiation effect due to x-ray irradiation has not been evaluated. Thus, we then conduct an x-ray irradiation experiment using an x-ray generator with a total dose of 10 krad at the SiO2 insulator, equivalent to 7 years in orbit. As a result of this experiment, the energy resolution in full-width half maximum for the 5.9 keV x-ray degrades by 17.8 % ± 2.8 % and the dark current increases by 89 % ± 13 %. We also investigate the physical mechanism of the increase in the dark current due to x-ray irradiation using technology computer-Aided design simulation. It is found that the increase in the dark current can be explained by the increase in the interface state density at the Si / SiO2 interface.
-
Detection of Recoil Electron Tracks using an SOI Pixel Sensor for an Advanced Compton Camera
Kagaya M., Katagiri H., Kato R., Tojo N., Takeda A., Shimazoe K., Tsuru T.G., Tanaka T., Uenomachi M., Zhang L.
2021 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2021 and 28th International Symposium on Room-Temperature Semiconductor Detectors, RTSD 2021年11月
記述言語:英語 掲載種別:研究論文(国際会議プロシーディングス) 出版者・発行元:2021 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2021 and 28th International Symposium on Room-Temperature Semiconductor Detectors, RTSD 2022
Sub-MeV line gamma-ray observations are important probes to elucidate various high-energy phenomena in astrophysics. An advanced Compton imaging technique is useful for detecting gamma rays in these bands. This camera can estimate an arrival direction of a gamma-ray event by event, thus, this camera can eliminate accidental events and false spots, which appear in a reconstructed image using a classical Compton camera. Furthermore, a semiconductor detector is essential for observing line gamma rays. In this study, we developed a prototype Compton camera using a silicon-on-insulator (SOI) pixel sensor. Using the prototype, we performed to detect recoil-electron tracks and estimated a recoil direction using a recoil-electron track. We succeeded in detecting electron tracks released from 511-keV gamma rays and estimating recoil directions. Furthermore, we reconstructed the arrival direction of a gamma ray and demonstrated to identify the source position by back-projection method. The angular resolution of an advanced Compton camera described two parameters, which is angular resolution measure (ARM) and scatter plane deviation (SPD). We obtained these tentative value from the reconstructed image. ARM and SPD are approximately 10° and 80-100°, respectively. For future plan, we will evaluate the quantitative detailed performances of the prototype under the various conditions.
-
Proton radiation hardness of x-ray SOI pixel sensors with pinned depleted diode structure
Hayashida M., Hagino K., Kohmura T., Kitajima M., Yarita K., Oono K., Negishi K., Tsuru T.G., Tanaka T., Uchida H., Kayama K., Kodama R., Mori K., Takeda A., Nishioka Y., Hida T., Yukumoto M., Arai Y., Kurachi I., Kitamura H., Kawahito S., Yasutomi K.
Journal of Astronomical Telescopes, Instruments, and Systems 7 ( 3 ) 2021年7月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Astronomical Telescopes, Instruments, and Systems
X-ray silicon-on-insulator (SOI) pixel sensors, "XRPIX,"are being developed for the next-generation x-ray astronomical satellite, "FORCE."The XRPIX is fabricated with the SOI technology, which makes it possible to integrate a high-resistivity Si sensor and a low-resistivity Si complementary metal oxide semiconductor (CMOS) circuit. The CMOS circuit in each pixel is equipped with a trigger function, allowing us to read out outputs only from the pixels with x-ray signals at the timing of x-ray detection. This function thus realizes high throughput and high time resolution, which enables to employ anti-coincidence technique for background rejection. A new series of XRPIX named XRPIX6E developed with a pinned depleted diode (PDD) structure improves spectral performance by suppressing the interference between the sensor and circuit layers. When semiconductor x-ray sensors are used in space, their spectral performance is generally degraded owing to the radiation damage caused by high-energy protons. Therefore, before using an XRPIX in space, it is necessary to evaluate the extent of degradation of its spectral performance by radiation damage. Thus, we performed a proton irradiation experiment for XRPIX6E for the first time at Heavy Ion Medical Accelerator in Chiba in the National Institute of Radiological Sciences. We irradiated XRPIX6E with high-energy protons with a total dose of up to 40 krad, equivalent to 400 years of irradiation in orbit. The 40-krad irradiation degraded the energy resolution of XRPIX6E by 25 ± 3 %, yielding an energy resolution of 260.1 ± 5.6 eV at the full-width half maximum for 5.9 keV X-rays. However, the value satisfies the requirement for FORCE, 300 eV at 6 keV, even after the irradiation. It was also found that the PDD XRPIX has enhanced radiation hardness compared to previous XRPIX devices. In addition, we investigated the degradation of the energy resolution; it was shown that the degradation would be due to increasing energy-independent components, e.g., readout noise.
-
Low-energy X-ray performance of SOI pixel sensors for astronomy, “XRPIX” 査読あり
Kodama R., Tsuru T.G., Tanaka T., Uchida H., Kayama K., Amano Y., Takeda A., Mori K., Nishioka Y., Yukumoto M., Hida T., Arai Y., Kurachi I., Kohmura T., Hagino K., Hayashida M., Kitajima M., Kawahito S., Yasutomi K., Kamehama H.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 986 2021年1月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
We have been developing a new type of X-ray pixel sensors, “XRPIX”, allowing us to perform imaging spectroscopy in the wide energy band of 1–20keV for the future Japanese X-ray satellite “FORCE”. The XRPIX devices are fabricated with complementary metal-oxide-semiconductor silicon-on-insulator technology, and have the “Event-Driven readout mode”, in which only a hit event is read out by using hit information from a trigger output function equipped with each pixel. This paper reports on the low-energy X-ray performance of the “XRPIX6E” device with a Pinned Depleted Diode (PDD) structure. The PDD structure especially reduces the readout noise, and hence is expected to largely improve the quantum efficiencies for low-energy X-rays. While F-K X-rays at 0.68keV and Al-K X-rays at 1.5keV are successfully detected in the “Frame readout mode”, in which all pixels are read out serially without using the trigger output function, the device is able to detect Al-K X-rays, but not F-K X-rays in the Event-Driven readout mode. Non-uniformity is observed in the counts maps of Al-K X-rays in the Event-Driven readout mode, which is due to region-to-region variation of the pedestal voltages at the input to the comparator circuit. The lowest available threshold energy is 1.1keV for a small region in the device where the non-uniformity is minimized. The noise of the charge sensitive amplifier at the sense node and the noise related to the trigger output function are ∼18e− (rms) and ∼13e− (rms), respectively.
-
Development of the detector simulation framework for the Wideband Hybrid X-ray Imager onboard FORCE 査読あり
Suzuki H., Tamba T., Odaka H., Bamba A., Hagino K., Takeda A., Mori K., Hida T., Yukumoto M., Nishioka Y., Tsuru T.G.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 979 2020年11月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2020 Elsevier B.V. FORCE is a Japan–US space-based astronomy mission for an X-ray imaging spectroscopy in an energy range of 1–80 keV. The Wideband Hybrid X-ray Imager (WHXI), which is the main focal plane detector, will use a hybrid semiconductor imager stack composed of silicon and cadmium telluride (CdTe). The silicon imager will be a certain type of the silicon-on-insulator (SOI) pixel sensor, named the X-ray pixel (XRPIX) series. Since the sensor has a small pixel size (30–36 μm) and a thick sensitive region (300–500 μm), understanding the detector response is not trivial and is important in order to optimize the camera design and to evaluate the scientific capabilities. We have developed a framework to simulate observations of celestial sources with semiconductor sensors. Our simulation framework was tested and validated by comparing our simulation results to laboratory measurements using the XRPIX 6H sensor. The simulator well reproduced the measurement results with reasonable physical parameters of the sensor including an electric field structure, a Coulomb repulsion effect on the carrier diffusion, and arrangement of the degraded regions. This framework is also applicable to future XRPIX updates including the one which will be part of the WHXI, as well as various types of semiconductor sensors.
-
Radiation damage effects on double-SOI pixel sensors for X-ray astronomy 査読あり
Hagino K., Yarita K., Negishi K., Oono K., Hayashida M., Kitajima M., Kohmura T., Tsuru T.G., Tanaka T., Uchida H., Kayama K., Amano Y., Kodama R., Takeda A., Mori K., Nishioka Y., Yukumoto M., Hida T., Arai Y., Kurachi I., Hamano T., Kitamura H.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 978 2020年10月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2020 Elsevier B.V. The X-ray SOI pixel sensor onboard the FORCE satellite will be placed in the low earth orbit and will consequently suffer from the radiation effects mainly caused by geomagnetically trapped cosmic-ray protons. Based on previous studies on the effects of radiation on SOI pixel sensors, the positive charges trapped in the oxide layer significantly affect the performance of the sensor. To improve the radiation hardness of the SOI pixel sensors, we introduced a double-SOI (D-SOI) structure containing an additional middle Si layer in the oxide layer. The negative potential applied on the middle Si layer compensates for the radiation effects, due to the trapped positive charges. Although the radiation hardness of the D-SOI pixel sensors for applications in high-energy accelerators has been evaluated, radiation effects for astronomical application in the D-SOI sensors has not been evaluated thus far. To evaluate the radiation effects of the D-SOI sensor, we perform an irradiation experiment using a 6-MeV proton beam with a total dose of ∼5krad, corresponding to a few tens of years of in-orbit operation. This experiment indicates an improvement in the radiation hardness of the X-ray D-SOI devices. On using an irradiation of 5 krad on the D-SOI device, the energy resolution in the full-width half maximum for the 5.9-keV X-ray increases by 7±2%, and the chip output gain decreases by 0.35±0.09%. The physical mechanism of the gain degradation is also investigated; it is found that the gain degradation is caused by an increase in the parasitic capacitance due to the enlarged buried n-well.
-
New pixel detector concept DuTiP for Belle II upgrade and the ILC with an SOI technology 査読あり
Ishikawa A., Arai Y., Baudot J., Haba J., Kachel M., Kurachi I., Li T., Ono S., Takayanagi T., Takeda A., Tsuboyama T., Yamada M.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 978 2020年10月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2020 Elsevier B.V. Belle II detector upgrade is being discussed aiming to collect five times larger integrated luminosity of 250 ab−1. The beam background level is expected five times higher than current design, thus a new pixel vertex detector with faster readout should be developed. We have invented a new pixel detector concept DuTiP for the Belle II upgrade which can be also used for the International Linear Collider (ILC) with small modifications. To realize the DuTiP concept, an SOI technology is chosen as a baseline with a pixel size of 35μm×35μm. The DuTiP concept and its application to a monolithic pixel detector in an SOI technology are explained.
-
Proton radiation hardness of x-ray SOI pixel detectors with pinned depleted diode structure 査読あり
Hayashida M., Kohmura T., Hagino K., Oono K., Negishi K., Yarita K., Kitajima M., Tsuru T.G., Tanaka T., Uchida H., Kayama K., Kodama R., Mori K., Takeda A., Nishioka Y., Hida T., Yukumoto M., Arai Y., Kurachi I., Hamano T., Kitamura H., Kawahito S., Yasutomi K.
Proceedings of SPIE - The International Society for Optical Engineering 11454 2020年7月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of SPIE - The International Society for Optical Engineering
We are developing an X-ray SOI pixel detector "XRPIX"for the next generation X-ray astronomical satellite "FORCE". XRPIX is the detector using SOI (Silicon-On-Insulator) technology which makes it possible to integrate a high-resistivity Si sensor part and a low-resistivity Si CMOS circuit part. The CMOS circuit is equipped with the trigger function, which can read out only the output signal of the pixel where the X-ray is incident. This function realizes high throughput and high time resolution, enabling the background rejection with anticoincidence technique. A new series of XRPIX named XRPIX6E, we developed, with a Pinned Depleted Diode (PDD) structure improves the spectral performance by suppressing the interference between the sensor layer and the circuit layer. When semiconductor X-ray detectors are used in space, it is known that their spectral performance is degraded due to radiation damage caused by high-energy protons. Therefore, before using XRPIX in space, it is necessary to evaluate how much the spectral performance will be degraded by radiation damage. Then we performed proton irradiation experiment for XRPIX6E for the first time at HIMAC in National Institute of Radiological Sciences. We irradiated XRPIX with high-energy protons up to a total dose of 40 krad, equivalent to 400 years irradiation in orbit. As a result, the energy resolution in full width half maximum at the 5:9 keV degrades by 25 ± 3%, however, is better than the required performance of FORCE, 300 eV at 6 keV. It was also found that the PDD structure XRPIX has better radiation hardness than the previous XRPIX series. In addition, We investigated about the degradation of the energy resolution; it was found that the degradation would be due to increasing energy independent components, for example, readout noise.
DOI: 10.1117/12.2562392
-
Simulation study on SOI based electron tracking Compton camera using deep learning method 査読あり
Shimazoe K., Toyoda K., Uenomachi M., Yoshihara Y., Takahashi H., Takeda A.
Journal of Instrumentation 15 ( 2 ) 2020年2月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2020 IOP Publishing Ltd and Sissa Medialab. Compton imaging is a promising method of sub MeV to a few MeV gamma-rays and expected to use in various application field, such as medical imaging, environmental monitoring and astrophysics. Several types of Compton camera has beed developed using different materials. One of the drawbacks in conventional Compton imaging is relatively low signal to background ratio caused by its projected Compton cones. Recoil electron tracking is one straight-forward way to improve the signal-to-background ratio, however, it is only realized in gaseous detectors. The realization of electron tracking in solid detectors is under investigation because of its short track in scatter materials. We demonstrated the capability of electron tracking in silicon-on-insulator (SOI) pixel detector with 30 μm pixels size. The extraction of ejected direction of recoil electrons in Compton scattering is an important problem. In this work, we investigated the use of deep learning for estimating the angle in plane and depth using Geant 4 Monte Carlo simulation. The effect of pixel size to the estimation accuracy and SPD is characterized for the application of actual silicon-on-insulator based SOI detectors. The imaging capability is also characterized using predicted recoil electron direction.
-
Belle II 検出器アップグレードに向けたピクセル崩壊点検出器の要求性能の研究およびSOI技術を用いた設計
幅 淳二, 新井 康夫, 石川 明正, 小野 峻, 倉知 郁生, 武田 彩希, 高柳 武浩, 坪山 透, 山田 美帆
日本物理学会講演概要集 75.1 ( 0 ) 79 - 79 2020年
-
軟X線/硬X線の広帯域を高感度観測する次世代衛星 FORCE:サイエンスとミッション提案の現状
中澤 知洋, 森 浩二, 鶴 剛, 上田 佳宏, 石田 学, 松本 浩典, 粟木 久光, 村上 弘志, 寺田 幸功, 久保田 あや, 馬場 彩, 小高 裕和, 谷津 陽一, 幸村 孝由, 萩野 浩一, 小林 翔悟, 内山 泰伸, 北山 哲, 高橋 忠幸, 渡辺 伸, 飯塚 亮, 山口 弘悦, 大橋 隆哉, 中嶋 大, 古澤 彰浩, 田中 孝明, 内田 裕之, 野田 博文, 常深 博, 伊藤 真之, 信川 正順, 信川 久実子, 太田 直美, 寺島 雄一, 深沢 泰司, 水野 恒史, 高橋 弘充, 大野 雅功, 武田 彩希, 岡島 崇, 他FORCE WG
日本物理学会講演概要集 75.1 523 - 523 2020年
-
Development of integration-type silicon-on-insulator monolithic pixel detectors using a float zone silicon 査読あり
Mitsui S., Arai Y., Miyoshi T., and Takeda A.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 2019年11月
記述言語:英語 掲載種別:研究論文(学術雑誌)
-
Sub-pixel response of double-SOI pixel sensors for X-ray astronomy 査読あり
Hagino K., Negishi K., Oono K., Yarita K., Kohmura T., Tsuru T., Tanaka T., Harada S., Kayama K., Matsumura H., Mori K., Takeda A., Nishioka Y., Yukumoto M., Fukuda K., Hida T., Arai Y., Kurachi I., and Kishimoto S.
Journal of Instrumentation 2019年10月
記述言語:英語 掲載種別:研究論文(学術雑誌)
-
Measurement of Charge Cloud Size in X-Ray SOI Pixel Sensors 査読あり
Hagino K., Oono K., Negishi K., Yarita K., Kohmura T., Tsuru T., Tanaka T., Uchida H., Harada S., Okuno T., Kayama K., Amano Y., Matsumura H., Mori K., Takeda A., Nishioka Y., Fukuda K., Hida T., Yukumoto M., Arai Y., Kurachi I., Miyoshi T., Kishimoto S.
IEEE Transactions on Nuclear Science 66 ( 7 ) 1897 - 1905 2019年7月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Transactions on Nuclear Science
© 1963-2012 IEEE. We report on a measurement of the size of charge clouds produced by X-ray photons in X-ray Silicon-on-insulator (SOI) pixel sensor named XRPIX. We carry out a beam scanning experiment of XRPIX using a monochromatic X-ray beam at 5.0 keV collimated to 10 μm with a 4-μmφ pinhole and obtain the spatial distribution of single-pixel events at a subpixel scale. The standard deviation of charge clouds of 5.0-keV X-ray is estimated to be σcloud=4.30± 0.07μm. Compared to the detector response simulation, the estimated charge cloud size is well explained by a combination of photoelectron range, thermal diffusion, and Coulomb repulsion. Moreover, by analyzing the fraction of multi-pixel events in various energies, we find that the energy dependence of the charge cloud size is also consistent with the simulation.
-
Kayama K., Tsuru T., Tanaka T., Uchida H., Harada S., Okuno T., Amano Y., Hiraga J., Yoshida M., Kamata Y., Sakuma S., Yuhi D., Urabe Y., Tsunemi H., Matsumura H., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H., Arai Y., Kurachi I., Takeda A., Mori K., Nishioka Y., Fukuda K., Hida T., Yukumoto M., Kohmura T., Hagino K., Oono K., Negishi K., Yarita K.
Journal of Instrumentation 14 ( 6 ) 2019年6月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2019 IOP Publishing Ltd and Sissa Medialab. We have been developing a monolithic active pixel sensor, "XRPIX", for the Japan led future X-ray astronomy mission "FORCE" observing the X-ray sky in the energy band of 1-80 keV with angular resolution of better than 15′′. XRPIX is an upper part of a stack of two sensors of an imager system onboard FORCE, and covers the X-ray energy band lower than 20 keV . The XRPIX device consists of a fully depleted high-resistivity silicon sensor layer for X-ray detection, a low resistivity silicon layer for CMOS readout circuit, and a buried oxide layer in between, which is fabricated with 0.2 μm CMOS silicon-on-insulator (SOI) technology. Each pixel has a trigger circuit with which we can achieve a 10 μs time resolution, a few orders of magnitude higher than that with X-ray astronomy CCDs. We recently introduced a new type of a device structure, a pinned depleted diode (PDD), in the XRPIX device, and succeeded in improving the spectral performance, especially in a readout mode using the trigger function. In this paper, we apply a mesh experiment to the XRPIX devices for the first time in order to study the spectral response of the PDD device at the subpixel resolution. We confirmed that the PDD structure solves the significant degradation of the charge collection efficiency at the pixel boundaries and in the region under the pixel circuits, which is found in the single SOI structure, the conventional type of the device structure. On the other hand, the spectral line profiles are skewed with low energy tails and the line peaks slightly shift near the pixel boundaries, which contribute to a degradation of the energy resolution.
-
Evaluation of Kyoto's event-driven X-ray astronomical SOI pixel sensor with a large imaging area 査読あり
Hayashi H., Tsuru T., Tanaka T., Uchida H., Matsumura H., Tachibana K., Harada S., Takeda A., Mori K., Nishioka Y., Takebayashi N., Yokoyama S., Fukuda K., Arai Y., Kurachi I., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H., Kohmura T., Hagino K., Negishi K., Oono K., Yarita K.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 400 - 403 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 We have been developing monolithic active pixel sensors, named “XRPIX” based on the silicon-on-insulator (SOI) pixel technology for future X-ray astronomy satellites. XRPIX has the function of event trigger and hit address outputs. This function allows us to read out analog signals only of hit pixels on trigger timing, which is referred to as the event-driven readout mode. Recently, we processed “XRPIX5b” with the largest imaging area of 21.9 mm × 13.8 mm in the XRPIX series. X-ray spectra are successfully obtained from all the pixels, and the readout noise is 46 e − (rms) in the frame readout mode. The gain variation was measured to be 1.2% (FWHM) among the pixels. We successfully obtain the X-ray image in the event-driven readout mode.
-
X-ray response evaluation in subpixel level for X-ray SOI pixel detectors 査読あり
Negishi K., Kohmura T., Hagino K., Kogiso T., Oono K., Yarita K., Sasaki A., Tamasawa K., Go Tsuru T., Tanaka T., Matsumura H., Tachibana K., Hayashi H., Harada S., Mori K., Takeda A., Nishioka Y., Takebayashi N., Yokoyama S., Fukuda K., Arai Y., Miyoshi T., Kishimoto S., Kurachi I.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 462 - 467 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 Elsevier B.V. We have been developing event-driven SOI Pixel Detectors, named “XRPIX” (X-ray soiPIXel) based on the silicon-on-insulator (SOI) pixel technology, for the future X-ray astronomical satellite with wide band coverage from 0.5keV to 40keV. XRPIX has event trigger output function at each pixel to acquire a good time resolution of a few μs and has Correlated Double Sampling function to reduce electric noises. The good time resolution enables the XRPIX to reduce Non X-ray Background in the high energy band above 10keV drastically by using anti-coincidence technique with active shield counters surrounding XRPIX. In order to increase the soft X-ray sensitivity, it is necessary to make the dead layer on the X-ray incident surface as thin as possible. Since XRPIX1b, which is a device at the initial stage of development, is a front-illuminated (FI) type of XRPIX, low energy X-ray photons are absorbed in the 8μm thick circuit layer, lowering the sensitivity in the soft X-ray band. Therefore, we developed a back-illuminated (BI) device XRPIX2b, and confirmed high detection efficiency down to 2.6keV, below which the efficiency is affected by the readout noise. In order to further improve the detection efficiency in the soft X-ray band, we developed a back-illuminated device XRPIX3b with lower readout noise. In this work, we irradiated 2–5keV X-ray beam collimated to 4μmϕ to the sensor layer side of the XRPIX3b at 6μm pitch. In this paper, we reported the uniformity of the relative detection efficiency, gain and energy resolution in the subpixel level for the first time. We also confirmed that the variation in the relative detection efficiency at the subpixel level reported by Matsumura (2015) has improved.
-
Total ionizing dose effects on the SOI pixel sensor for X-ray astronomical use 査読あり
Mori K., Nishioka Y., Takeda A., Takebayashi N., Takenaka R., Sakakura S., Yokoyama S., Fukuda K., Yukumoto M., Hida T., Tsuru T., Tanaka T., Matsumura H., Hayashi H., Kohmura T., Nakashima S., Arai Y., Kurachi I.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 473 - 479 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 Elsevier B.V. We report on total ionizing dose effects on the X-ray SOI pixel sensor, XRPIX. XRPIX has been developed as an imaging spectrometer for X-ray astronomical use in space. Front- and back-illuminated (FI and BI) devices were irradiated with hard X-rays from an X-ray tube operated at 30 kV with a Molybdenum target. We found that the degradation rate of the readout noise of the BI device was approximately three times slower than that of the FI device as a function of radiation exposure. Those of both type of devices, however, were virtually identical when the readout noise was evaluated as a function of the absorbed dose at the buried oxide layer, D BOX . The pedestal and analog-to-digital conversion gain also displayed similar tendencies. These results demonstrate that BI type devices have a higher radiation tolerance as a focal plane sensor of an X-ray mirror and the radiation tolerance of XRPIX devices is governed by D BOX . The readout noise was stable up to about 1 krad in D BOX , increased by about 10% at 10 krad in D BOX , and continued to increase under further irradiation. If we employ an X-ray mirror with a half-power diameter of 10 arcsec and a focal length of 10 m, 10 krad in D BOX , a reasonable threshold of radiation tolerance in this experiment, is equivalent to more than three years in orbit, typically required of space-borne sensors.
-
Studies of radioactive background in SOI pixel detector for solar axion search experiment 査読あり
Onuki Y., Grimaldo J., Ose T., Aihara H., Inoue Y., Kamiya Y., Shimazoe K., Tsuru T., Tanaka T., Miuchi K., Takeda A., Arai Y.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 448 - 451 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 Elsevier B.V. An application of a modern noble pixel detector, XRPIX series, for solar KSVZ axion search experiment is being developed. A low radioactive background is necessary in the detector volume for the axion search. We surveyed the radioactivity of all peripheral components mounted on the detector using an HPGe detector. The results are used as an input for a GEANT4 Monte Carlo simulation to study the background in the experiment. This paper describes the expected background and the simulated sensitivity of stacked XRPIX detector currently under development.
-
Proton radiation damage experiment for X-ray SOI pixel detectors 査読あり
Yarita K., Kohmura T., Hagino K., Kogiso T., Oono K., Negishi K., Tamasawa K., Sasaki A., Yoshiki S., Tsuru T., Tanaka T., Matsumura H., Tachibana K., Hayashi H., Harada S., Takeda A., Mori K., Nishioka Y., Takebayashi N., Yokoyama S., Fukuda K., Arai Y., Miyoshi T., Kurachi I., Hamano T.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 457 - 461 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 Elsevier B.V. In low earth orbit, there are many cosmic rays composed primarily of high energy protons. These cosmic rays cause surface and bulk radiation effects, resulting in degradation of detector performance. Quantitative evaluation of radiation hardness is essential in development of X-ray detectors for astronomical satellites. We performed proton irradiation experiments on newly developed X-ray detectors called XRPIX based on silicon-on-insulator technology at HIMAC in National Institute of Radiological Sciences. We irradiated 6 MeV protons with a total dose of 0.5 krad, equivalent to 6 years irradiation in orbit. As a result, the gain increases by 0.2% and the energy resolution degrades by 0.5%. Finally we irradiated protons up to 20 krad and found that detector performance degraded significantly at 5 krad. With 5 krad irradiation corresponding to 60 years in orbit, the gain increases by 0.7% and the energy resolution worsens by 10%. By decomposing into noise components, we found that the increase of the circuit noise is dominant in the degradation of the energy resolution.
-
Harada S., Tsuru T., Tanaka T., Uchida H., Matsumura H., Tachibana K., Hayashi H., Takeda A., Mori K., Nishioka Y., Takebayashi N., Yokoyama S., Fukuda K., Arai Y., Kurachi I., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H., Kohmura T., Hagino K., Negishi K., Oono K., Yarita K.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 924 468 - 472 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2018 Elsevier B.V. We have been developing event driven X-ray Silicon-On-Insulator (SOI) pixel sensors, called “XRPIX” for the next generation of X-ray astronomy satellites. XRPIX is a monolithic active pixel sensor, fabricated using the SOI CMOS technology, and is equipped with the so-called “Event-Driven readout” which allows reading out only hit pixels by using the trigger circuit implemented in each pixel. The current version of XRPIX has lower spectral performance in the Event-Driven readout mode than in the Frame readout mode, which is due to the interference between the sensor layer and the circuit layer. The interference also lowers the gain. In order to suppress the interference, we developed a new device, “XRPIX6E” equipped with the Pinned Depleted Diode structure. A sufficiently highly-doped buried p-well is formed at the interface between the buried oxide layer and the sensor layer, and acts as a shield layer. XRPIX6E exhibits improved spectral performances both in the Event-Driven readout mode and in the Frame readout mode in comparison to previous devices. The energy resolutions in full width at half maximum at 6.4 keV are 236 ± 1 eV and 335 ± 4 eV in the Frame and Event-Driven readout modes, respectively. There are differences between the readout noise and the spectral performance in the two modes, which suggests that some mechanism still degrades the performance in the Event-Driven readout mode.
-
Kanemaru Y., Sato J., Mori K., Nakajima H., Nishioka Y., Takeda A., Hayashida K., Matsumoto H., Iwagaki J., Okazaki K., Asakura K., Yoneyama T., Uchida H., Okon H., Tanaka T., Tsuru T., Tomida H., Shimoi T., Kohmura T., Hagino K., Murakami H., Kobayashi S., Yamauchi M., Hatsukade I., Nobukawa M., Nobukawa K., Hiraga J., Uchiyama H., Yamaoka K., Ozaki M., Dotani T., Tsunemi H., Hamano T.
Journal of Instrumentation 14 ( 4 ) 2019年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2019 IOP Publishing Ltd and Sissa Medialab. We report the radiation hardness of a p-channel CCD developed for the X-ray CCD camera onboard the XRISM satellite. This CCD has basically the same characteristics as the one used in the previous Hitomi satellite, but newly employs a notch structure of potential for signal charges by increasing the implant concentration in the channel . The new device was exposed up to approximately 7.9 × 1010 protons cm-2 at 100 MeV . The charge transfer inefficiency was estimated as a function of proton fluence with an 55Fe source. A device without the notch structure was also examined for comparison. The result shows that the notch device has a significantly higher radiation hardness than those without the notch structure including the device adopted for Hitomi. This proves that the new CCD is radiation tolerant for space applications with a sufficient margin.
-
Kagaya M., Katagiri H., Tojo N., Kato R., Tsuru T.G., Takeda A., Arai Y.
2018 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2018 - Proceedings 2018年11月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:2018 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2018 - Proceedings
© 2018 IEEE. In the fields of astrophysics and nuclear medicine diagnostics, the use of a 511-keV line gamma rays probe is indispensable. Compton-imaging techniques are suitable for measuring 511-keV line gamma rays because of the high probability of Compton scattering at this energy level. However, a reconstructed image obtained by a traditional Compton camera has false spots because this camera reconstructs an image with smeared rings. On the other hand, an advanced Compton camera can enhance the angular resolution and reduce the background by detecting recoil electron tracks. We focus on a silicon-on-insulator (SOI) pixel sensor with 30 m cells because of its small pixel pitch and high-energy resolution. In this study, we developed a prototype of an advanced Compton camera using an SOI sensor and evaluated its performance for detecting the recoil electron tracks of 511-keV gamma rays.
-
Performance of SOI Pixel Sensors Developed for X-ray Astronomy
Tanaka T., Tsuru T.G., Uchida H., Harada S., Okuno T., Kayama K., Amano Y., Matsumura H., Takeda A., Mori K., Nishioka Y., Fukuda K., Hida T., Yukumoto M., Arai Y., Kurachi I., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H., Kohmura T., Hagino K., Negishi K., Oono K., Yarita K.
2018 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2018 - Proceedings 2018年11月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:2018 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2018 - Proceedings
© 2018 IEEE. We have been developing monolithic active pixel sensors for X-rays based on the silicon-on-insulator technology. Our device consists of a low-resistivity Si layer for readout CMOS electronics, a high-resistivity Si sensor layer, and a SiO2 layer between them. This configuration allows us both high-speed readout circuits and a thick (on the order of 100 m) depletion layer in a monolithic device. Each pixel circuit contains a trigger output function, with which we can achieve a time resolution of ≲ 10 s. One of our key development items is improvement of the energy resolution. We recently fabricated a device named XRPIX6E, to which we introduced a pinned depleted diode (PDD) structure. The structure reduces the capacitance coupling between the sensing area in the sensor layer and the pixel circuit, which degrades the spectral performance. With XRPIX6E, we achieve an energy resolution of ~ 150 eV in full width at half maximum for 6.4-keV X-rays. In addition to the good energy resolution, a large imaging area is required for practical use. We developed and tested XRPIX5b, which has an imaging area size of 21.9 mm 13.8 mm and is the largest device that we ever fabricated. We successfully obtain X-ray data from almost all the 608 384 pixels with high uniformity.
-
Shrestha S., Kawahito S., Kamehama H., Nakanishi S., Yasutomi K., Kagawa K., Teranishi N., Takeda A., Tsuru T., Kurachi I., Arai Y.
Sensors (Switzerland) 18 ( 6 ) 2018年6月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Sensors (Switzerland)
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. In this paper, we report on the development of a monolithic active pixel sensor for X-ray imaging using 0.2 µm fully depleted silicon-on-insulator (SOI)-based technology to support next generation astronomical satellite missions. Detail regarding low-noise dual-gain SOI based pixels with a charge sensitive amplifier and pinned depleted diode sensor structure is presented. The proposed multi-well sensor structure underneath the fully-depleted SOI allows the design of a detector with low node capacitance and high charge collection efficiency. Configurations for achieving very high charge-to-voltage conversion gain of 52 µV/e− and 187 µV/e− are demonstrated. Furthermore, in-pixel dual gain selection is used for low-noise and wide dynamic range X-ray energy detection. A technique to improve the noise performance by removing correlated system noise leads to an improvement in the spectroscopic performance of the measured X-ray energy. Taken together, the implemented chip has low dark current (44.8 pA/cm2 at −30°C), improved noise performance (8.5 e− rms for high gain and 11.7 e− rms for low gain), and better energy resolution of 2.89% (171 eV FWHM) at 5.9 keV using55 Fe and 1.67% (234 eV FWHM) at 13.95 keV using241 Am.
DOI: 10.3390/s18061789
-
Kamehama H., Kawahito S., Shrestha S., Nakanishi S., Yasutomi K., Takeda A., Tsuru T., Arai Y.
Sensors (Switzerland) 18 ( 1 ) 2018年1月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Sensors (Switzerland)
© 2017 by the authors. Licensee MDPI, Basel, Switzerland. This paper presents a novel full-depletion Si X-ray detector based on silicon-on-insulator pixel (SOIPIX) technology using a pinned depleted diode structure, named the SOIPIX-PDD. The SOIPIX-PDD greatly reduces stray capacitance at the charge sensing node, the dark current of the detector, and capacitive coupling between the sensing node and SOI circuits. These features of the SOIPIX-PDD lead to low read noise, resulting high X-ray energy resolution and stable operation of the pixel. The back-gate surface pinning structure using neutralized p-well at the back-gate surface and depleted n-well underneath the p-well for all the pixel area other than the charge sensing node is also essential for preventing hole injection from the p-well by making the potential barrier to hole, reducing dark current from the Si-SiO2 interface and creating lateral drift field to gather signal electrons in the pixel area into the small charge sensing node. A prototype chip using 0.2 µm SOI technology shows very low readout noise of 11.0 e-rms, low dark current density of 56 pA/cm2 at -35°C and the energy resolution of 200 eV(FWHM) at 5.9 keV and 280 eV (FWHM) at 13.95 keV.
DOI: 10.3390/s18010027
-
Kyoto's event-driven x-ray astronomy SOI pixel sensor for the FORCE mission
Tsuru T., Hayashi H., Tachibana K., Harada S., Uchida H., Tanaka T., Arai Y., Kurachi I., Mori K., Takeda A., Nishioka Y., Takebayashi N., Yokoyama S., Fukuda K., Kohmura T., Hagino K., Ohno K., Negishi K., Yarita K., Kawahito S., Kagawa K., Yasutomi K., Shrestha S., Nakanishi S., Kamehama H., Matsumura H.
Proceedings of SPIE - The International Society for Optical Engineering 10709 2018年
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of SPIE - The International Society for Optical Engineering
© 2018 SPIE. We have been developing monolithic active pixel sensors, X-ray Astronomy SOI pixel sensors, XRPIXs, based on a Silicon-On-Insulator (SOI) CMOS technology as soft X-ray sensors for a future Japanese mission, FORCE (Focusing On Relativistic universe and Cosmic Evolution). The mission is characterized by broadband (1-80 keV) X-ray imaging spectroscopy with high angular resolution (< 15 arcsec), with which we can achieve about ten times higher sensitivity in comparison to the previous missions above 10 keV. Immediate readout of only those pixels hit by an X-ray is available by an event trigger output function implemented in each pixel with the time resolution higher than 10 μsec (Event-Driven readout mode). It allows us to do fast timing observation and also reduces non-X-ray background dominating at a high X-ray energy band above 5{10 keV by adopting an anti-coincidence technique. In this paper, we introduce our latest results from the developments of the XRPIXs. (1) We successfully developed a 3-side buttable back-side illumination device with an imaging area size of 21.9 mm × 13.8 mm and an pixel size of 36 μm × 36 μm. The X-ray throughput with the device reaches higher than 0.57 kHz in the Event-Driven readout mode. (2) We developed a device using the double SOI structure and found that the structure improves the spectral performance in the Event-Driven readout mode by suppressing the capacitive coupling interference between the sensor and circuit layers. (3) We also developed a new device equipped with the Pinned Depleted Diode structure and confirmed that the structure reduces the dark current generated at the interface region between the sensor and the SiO2 insulator layers. The device shows an energy resolution of 216 eV in FWHM at 6.4 keV in the Event-Driven readout mode.
DOI: 10.1117/12.2312098
-
Soft x-ray imaging telescope (Xtend) onboard X-ray Astronomy Recovery Mission (XARM)
Hayashida K., Tomida H., Mori K., Nakajima H., Tanaka T., Uchida H., Tsuru T., Murakami H., Okajima T., Kohmura T., Hagino K., Kobayashi S., Ishida M., Maeda Y., Uchiyama H., Yamaoka K., Matsumoto H., Nobukawa M., Nobukawa K., Hiraga J., Yamauchi M., Hatsukade I., Soong Y., Mori H., Hayashi T., Tsunemi H., Ozaki M., Dotani T., Iwagaki J., Yoneyama T., Okazaki K., Asakura K., Onishi S., Kanemaru Y., Sato J., Nishioka Y., Takeda A., Okon H., Yoshida M., Shimoi T.
Proceedings of SPIE - The International Society for Optical Engineering 10699 2018年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of SPIE - The International Society for Optical Engineering
© 2018 SPIE. X-ray Astronomy Recovery Mission (XARM) scheduled to be launched in early 2020's carries two soft X-ray telescopes. One is Resolve consisting of a soft X-ray mirror and a micro calorimeter array, and the other is Soft X-ray Imaging Telescope (Xtend), a combination of an X-ray mirror assembly (XMA) and an X-ray CCD camera (SXI). Xtend covers a field of view (FOV) of 38′ × 38′, much larger than that of Resolve (3′ × 3 ′) with moderate energy resolution in the energy band from 0.4 keV to 13 keV, which is similar to that of Resolve (from 0.3 keV to 12 keV). Simultaneous observations of both telescopes provide complimentary data of X-ray sources in their FOV. In particular, monitoring X-ray sources outside the Resolve FOV but inside the Xtend FOV is important to enhance the reliability of super high resolution spectra obtained with Resolve. Xtend is also expected to be one of the best instruments for low surface brightness X-ray emissions with its low non X-ray background level, which is comparable to that of Suzaku XIS. The design of Xtend is almost identical to those of Soft X-ray Telescope (SXT) and Soft X-ray Imager (SXI) both on board the Hitomi satellite. However, several mandatory updates are included. Updates for the CCD chips are verified with experiment using test CCD chips before finalizing the design of the flight model CCD. Fabrication of the foils for XMA has started, and flight model production of the SXI is almost ready.
DOI: 10.1117/12.2311446
-
Development of electron-tracking Compton imaging system with 30-μm SOI pixel sensor
Yoshihara Y., Shimazoe K., Mizumachi Y., Takahashi H., Kamada K., Takeda A., Tsuru T., Arai Y.
Journal of Instrumentation 12 ( 1 ) 2017年1月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2017 IOP Publishing Ltd and Sissa Medialab srl. Compton imaging is a useful method to localize gamma sources without using mechanical collimators. In conventional Compton imaging, the incident directions of gamma rays are estimated in a cone for each event by analyzing the sequence of interactions of each gamma ray followed by Compton kinematics. Since the information of the ejection directions of the recoil electrons is lost, many artifacts in the shape of cone traces are generated, which reduces signal-to-noise ratio (SNR) and angular resolution. We have developed an advanced Compton imaging system with the capability of tracking recoil electrons by using a combination of a trigger-mode silicon-on-insulator (SOI) pixel detector and a GAGG detector. This system covers the 660-1330 keV energy range for localization of contamination nuclides such as 137Cs and 134Cs inside the Fukushima Daiichi Nuclear Power Plant in Japan. The ejection directions of recoil electrons caused by Compton scattering are detected on the micro-pixelated SOI detector, which can theoretically be used to determine the incident directions of the gamma rays in a line for each event and can reduce the appearance of artifacts. We obtained 2-D reconstructed images from the first iteration of the proposed system for 137Cs, and the SNR and angular resolution were enhanced compared with those of conventional Compton imaging systems.
-
Ohmura S., Tsuru T., Tanaka T., Uchida H., Takeda A., Matsumura H., Ito M., Arai Y., Kurachi I., Miyoshi T., Nakashima S., Mori K., Nishioka Y., Takebayashi N., Noda K., Kohmura T., Tamasawa K., Ozawa Y., Sato T., Konno T., Kawahito S., Kagawa K., Yasutomi K., Kamehama H., Shrestha S., Hara K., Honda S.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 831 61 - 64 2016年9月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2016 Elsevier B.V. We have been developing silicon-on-insulator pixel sensors, “XRPIXs,” for future X-ray astronomy satellites. XRPIXs are equipped with a function of “event-driven readout,” with which we can read out only hit pixels by trigger signals and hence realize good time resolution reaching ∼10μs. The current version of XRPIX suffers from a problem that the spectral performance degrades in the event-driven readout mode compared to the frame-readout mode, in which all the pixels are read out serially. Previous studies have clarified that one of the causes is capacitive coupling between the sense node and the trigger signal line in the circuit layer. In order to solve the problem, we adopt the Double SOI structure having a middle silicon layer between the circuit and the sensor layers. We expect the middle silicon layer to work as an electrostatic shield and reduces the capacitive coupling. In this paper, we report the spectroscopic performance of XRPIX with the middle silicon layer. We successfully reduce the capacitive coupling and the readout noise.
-
The first back-side illuminated types of Kyoto's X-ray astronomy SOIPIX
Itou M., Tsuru T., Tanaka T., Takeda A., Matsumura H., Ohmura S., Uchida H., Nakashima S., Arai Y., Kurachi I., Mori K., Takenaka R., Nishioka Y., Kohmura T., Tamasawa K., Tindall C.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 831 55 - 60 2016年9月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2016 Elsevier B.V. We have been developing Kyoto's X-ray astronomy SOI pixel sensors, called “XRPIX”, aiming to extend the frontiers of X-ray astronomy with the wide-band imaging spectroscopy in the 0.5–40 keV band. A dead layer on the X-ray incident surface should ideally be as thin as possible to achieve a high sensitivity below 1 keV, and the depletion layer is required to be thick enough to detect 40 keV X-rays. Thus, we have started developing fully-depleted back-side illuminated (BI) types of XRPIXs. This paper reports on our first two BI devices and their X-ray evaluation (2.6–12 keV). The device named “XRPIX2b-FZ-LA” successfully reaches a full depletion with a thickness of 500 μm. On the other hand, it has a dead layer with a thickness of 1.1–1.5 μm and struggles to achieve the requirement of 1.0 μm. The other device named “XRPIX2b-CZ-PZ”, which is applied with a thin Si sensor-layer and an improved back-side process, is found to satisfy the requirement with its thickness of 0.9–1.0 μm, including Al optical blocking filter of 0.2 μm, although the Si sensor-layer is rather thin with 62 μm. We also describe in this paper the X-ray calibration system that we have built for the X-ray evaluation of XRPIXs.
-
Radiation damage in transistors fabricated with lapis semiconductor 200 nm FD-SOI technology
Glab S., Arai Y., Baszczyk M., Bugiel S., Dasgupta R., Dorosz P., Idzik M., Kapusta P., Kucewicz W., Mierzwinska G., Mik L., Miyoshi T., Ptaszkiewicz M., Rydygier M., Sapor M., Swakon J., Takeda A.
2014 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2014 2016年3月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:2014 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2014
© 2014 IEEE. The paper presents radiation tolerance of the transistor TEG (TrTEG5) test structure fabricated in 200 nm fully depleted silicon on insulator technology dedicated to production of SOI detectors. The chip was irradiated with 60Cobalt gamma-ray source to total dose of 1.175 kGy at a rate of 67.8 Gy/h. During irradiation, current-voltage characteristics of seventeen different transistors were measured so as to investigate factors affecting radiation resistance. Transistors' threshold voltage shift and transconductance change as a function of the deposited dose are presented. After irradiation all transistors manifested correct operation and threshold voltage change of around 200 mV fall within the limits of specified technological mismatch.
-
Electron Pattern Recognition using trigger mode SOI pixel sensor for Advanced Compton Imaging
Shimazoe K., Yoshihara Y., Fairuz A., Koyama A., Takahashi H., Takeda A., Tsuru T., Arai Y.
Journal of Instrumentation 11 ( 2 ) 2016年2月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2016 IOP Publishing Ltd and Sissa Medialab srl. Compton imaging is a useful method for localizing sub MeV to a few MeV gamma-rays and widely used for environmental and medical applications. The direction of recoiled electrons in Compton scattering process provides the additional information to limit the Compton cones and increases the sensitivity in the system. The capability of recoiled electron tracking using trigger-mode Silicon-On-Insulator (SOI) sensor is investigated with various radiation sources. The trigger-mode SOI sensor consists of 144 by 144 active pixels with 30 μm cells and the thickness of sensor is 500 μm. The sensor generates the digital output when it is hit by gamma-rays and 25 by 25 pixel pattern of surrounding the triggered pixel is readout to extract the recoiled electron track. The electron track is successfully observed for 60Co and 137Cs sources, which provides useful information for future electron tracking Compton camera.
-
Improving charge-collection efficiency of SOI pixel sensors for X-ray astronomy
Matsumura H., Tsuru T., Tanaka T., Takeda A., Arai Y., Mori K., Nishioka Y., Takenaka R., Kohmura T., Nakashima S., Hatsui T., Kohmura Y., Takei D., Kameshima T.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 794 255 - 259 2015年7月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2015 Elsevier B.V. Abstract We have been developing a new type of active pixel sensor, referred to as "XRPIX" for future X-ray astronomy satellites on the basis of silicon-on-insulator CMOS technology. The problem on our previous device, XRPIX1b, was degradation of the charge-collection efficiency (CCE) at pixel borders. In order to investigate the non-uniformity of the CCE within a pixel, we measured sub-pixel response with X-ray beams whose diameters are 10μmΦ at SPring-8. We found that the X-ray detection efficiency and CCE degrade in the sensor region under the pixel circuitry placed outside the buried p-wells (BPW). A 2D simulation of the electric fields with the semiconductor device simulator HyDeLEOS shows that the isolated pixel circuitry outside the BPW makes local minimums in the electric potentials at the interface between the sensor and buried oxide layers, where a part of charge is trapped and is not collected to the BPW. Based on this result, we modified the placement of the in-pixel circuitry in the next device, XRPIX2b, for the electric fields to be converged toward the BPW, and confirmed that the CCE at pixel borders is successfully improved.
-
Takeda A., Tsuru T., Tanaka T., Uchida H., Matsumura H., Arai Y., Mori K., Nishioka Y., Takenaka R., Kohmura T., Nakashima S., Kawahito S., Kagawa K., Yasutomi K., Kamehama H., Shrestha S.
Journal of Instrumentation 10 ( 6 ) 2015年6月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2015 IOP Publishing Ltd and Sissa Medialab srl. We have been developing monolithic active pixel sensors series, named ''XRPIX'', based on the silicon-on-insulator (SOI) pixel technology, for future X-ray astronomical satellites. The XRPIX series offers high coincidence time resolution (∼ 1 μs), superior readout time (∼ 10 μs), and a wide energy range (0.5-40 keV) . In the previous study, we successfully demonstrated X-ray detection by event-driven readout of XRPIX2b. We here report recent improvements in spectroscopic performance. We successfully increased the gain and reduced the readout noise in XRPIX2b by decreasing the parasitic capacitance of the sense-node originated in the buried p-well (BPW) . On the other hand, we found significant tail structures in the spectral response due to the loss of the charge collection efficiency when a small BPW is employed. Thus, we increased the gain in XRPIX3b by introducing in-pixel charge sensitive amplifiers instead of having even smaller BPW . We finally achieved the readout noise of 35 e<sup>-</sup> (rms) and the energy resolution of 320 eV (FWHM) at 6 keV without significant loss of the charge collection efficiency.
-
Characterization of high resolution CMOS monolithic active pixel detector in SOI technology
Ahmed M., Arai Y., Glab S., Idzik M., Kapusta P., Miyoshi T., Takeda A., Turala M.
Journal of Instrumentation 10 ( 5 ) 2015年5月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
© 2015 IOP Publishing Ltd and Sissa Medialab srl. Novel CMOS monolithic pixel detectors designed at KEK and fabricated at Lapis Semiconductor in 0.2 μm Silicon-on-Insulator (SOI) technology are presented. A thin layer of silicon oxide separates high and low resistivity silicon layers, allowing for optimization of design of detector and readout parts. Shallow wells buried under the oxide in the detector part screen the entire pixel electronics from electrical field applied to the detector. Several integration type SOI pixel detectors have been developed with pixel sizes 8-20 μm. The general features of 14 × 14 μm2 detectors designed on different wafers (CZ-n, FZ-n and FZ-p) were measured and compared. The detector performance was studied under irradiation with visible and infra-red laser, and also X-ray ionizing source. Using X-rays from an Am-241 source the noise of readout electronics was measured at different working conditions, showing the ENC in the range of 88-120 e-. The pixel current was calculated from average DC pedestal shift while varying the pixel integration time. The operation of the detector was studied under partial and full depletion conditions. The effects of temperature and detector bias voltage on noise and leakage current were studied. Characteristics of an ADC integrated in the front-end chip are also presented.
-
X-ray generation by inverse Compton scattering at the superconducting RF test facility
Shimizu H., Akemoto M., Arai Y., Araki S., Aryshev A., Fukuda M., Fukuda S., Haba J., Hara K., Hayano H., Higashi Y., Honda Y., Honma T., Kako E., Kojima Y., Kondo Y., Lekomtsev K., Matsumoto T., Michizono S., Miyoshi T., Nakai H., Nakajima H., Nakanishi K., Noguchi S., Okugi T., Sato M., Shevelev M., Shishido T., Takenaka T., Tsuchiya K., Urakawa J., Watanabe K., Yamaguchi S., Yamamoto A., Yamamoto Y., Sakaue K., Hosoda S., Iijima H., Kuriki M., Tanaka R., Kuramoto A., Omet M., Takeda A.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 772 26 - 33 2015年2月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2014 Elsevier B.V. All rights reserved. Quasi-monochromatic X-rays with high brightness have a broad range of applications in fields such as life sciences, bio-, medical applications, and microlithography. One method for generating such X-rays is via inverse Compton scattering (ICS). X-ray generation experiments using ICS were carried out at the superconducting RF test facility (STF) accelerator at KEK. A new beam line, newly developed four-mirror optical cavity system, and new X-ray detector system were prepared for experiments downstream section of the STF electron accelerator. Amplified pulsed photons were accumulated into a four-mirror optical cavity and collided with an incoming 40 MeV electron beam. The generated X-rays were detected using a microchannel plate (MCP) detector for X-ray yield measurements and a new silicon-on-insulator (SOI) detector system for energy measurements. The detected X-ray yield by the MCP detector was 1756.8±272.2 photons/(244 electron bunches). To extrapolate this result to 1 ms train length under 5 Hz operations, 4.60×105 photons/1%-bandwidth were obtained. The peak X-ray energy, which was confirmed by the SOI detector, was 29 keV, and this is consistent with ICS X-rays.
-
Shrestha S., Kamehama H., Kawahito S., Yasutomi K., Kagawa K., Takeda A., Tsuru T., Arai Y.
Proceedings of SPIE - The International Society for Optical Engineering 9593 2015年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of SPIE - The International Society for Optical Engineering
© 2015 SPIE. This paper presents a low-noise wide-dynamic-range pixel design for a high-energy particle detector in astronomical applications. A silicon on insulator (SOI) based detector is used for the detection of wide energy range of high energy particles (mainly for X-ray). The sensor has a thin layer of SOI CMOS readout circuitry and a thick layer of high-resistivity detector vertically stacked in a single chip. Pixel circuits are divided into two parts; signal sensing circuit and event detection circuit. The event detection circuit consisting of a comparator and logic circuits which detect the incidence of high energy particle categorizes the incident photon it into two energy groups using an appropriate energy threshold and generate a two-bit code for an event and energy level. The code for energy level is then used for selection of the gain of the in-pixel amplifier for the detected signal, providing a function of high-dynamic-range signal measurement. The two-bit code for the event and energy level is scanned in the event scanning block and the signals from the hit pixels only are read out. The variable-gain in-pixel amplifier uses a continuous integrator and integration-time control for the variable gain. The proposed design allows the small signal detection and wide dynamic range due to the adaptive gain technique and capability of correlated double sampling (CDS) technique of kTC noise canceling of the charge detector.
DOI: 10.1117/12.2188019
-
Investigation of charge-collection efficiency of Kyoto's X-ray astronomical SOI pixel sensors, XRPIX
Matsumura H., Tsuru T., Tanaka T., Nakashima S., Ryu S., Takeda A., Arai Y., Miyoshi T.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 765 183 - 186 2014年11月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
© 2014 Elsevier B.V. We are developing a monolithic active pixel sensor referred to as XRPIX for X-ray astronomy on the basis of silicon-on-insulator CMOS technology. A crucial issue in our recent development is the impact of incomplete charge collection on the spectroscopic performance. In this paper, we report the spectral responses of several devices having different intra-pixel structures or produced from different wafers. We found that an emission line spectrum exhibits large low-energy tails when the size of the buried p-well, which acts as the charge-collection node, is small. Moreover, in charge sharing events, the peak channels of the emission lines shift toward channels lower than those without charge sharing. This peak shift is more pronounced as the distance between the pixel center and the position of incident photon increases. This suggests that the charge-collection efficiency is degraded at the pixel boundary. We also found that the charge-collection efficiency depends on the strength of the electric field at the interface of the depletion and insulator layers.
-
Bandgap voltage reference and temperature sensor in novel SOI technology 国際共著
Glab S., Baszczyk M., Dorosz P., Idzik M., Kucewicz W., Sapor M., Kapusta P., Arai Y., Miyoshi T., Takeda A.
2014 International Conference on Signals and Electronic Systems, ICSES 2014 2014年11月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:2014 International Conference on Signals and Electronic Systems, ICSES 2014
© 2014 IEEE. A bandgap voltage reference together with absolute temperature sensor (PTAT) designed in 200 nm SOI technology is presented in this paper. Three slightly different versions were designed to verify the diode models available in the SOI process. For more extensive SOI process study the chip was fabricated on three different substrates. The bandgap reference circuit generates Vref = 1.27 V with 10 mV chip to chip spread. The best bandgap version has temperature coefficient -35 μV/K. Circuit design, simulations and comparison with measured performance are presented.
-
Synthetizable digital library created to facilitate design of SOI detectors in 200 nm SOI technology
Glab S., Baszczyk M., Dorosz P., Idzik M., Kucewicz W., Sapor M., Kapusta P., Arai Y., Miyoshi T., Takeda A.
2014 International Conference on Signals and Electronic Systems, ICSES 2014 2014年11月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:2014 International Conference on Signals and Electronic Systems, ICSES 2014
© 2014 IEEE. A digital library designed in 200 nm fully depleted silicon on insulator (FD-SOI) technology is presented in this paper. For the purpose of a new technology the digital library containing 93 elements was designed. Created library allows automatic synthesis of digital blocks based on their description in hardware description languages (HDL). To preserve area occupied by each library element, height of 7.68 μm was chosen for all layout cells. The paper presents designed digital library., compares its performance with digital library made in Austria Mikro Systeme (AMS) 0.35 μm and shows test structures' measurements results.
-
Miyoshi T., Ahmed M., Arai Y., Fujita Y., Ikemoto Y., Takeda A., Tauchi K.
Journal of Instrumentation 9 ( 5 ) 2014年5月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Journal of Instrumentation
We are developing monolithic pixel detector using fully-depleted (FD) silicon-on-insulator (SOI) pixel process technology. The SOI substrate is high resistivity silicon with p-n junctions and another layer is a low resistivity silicon for SOI-CMOS circuitry. Tungsten vias are used for the connection between two silicons. Since flip-chip bump bonding process is not used, high sensor gain in a small pixel area can be obtained. In 2010 and 2011, high-resolution integration-type SOI pixel sensors, DIPIX and INTPIX5, have been developed. The characterizations by evaluating pixel-to-pixel crosstalk, quantum efficiency (QE), dark noise, and energy resolution were done. A phase-contrast imaging was demonstrated using the INTPIX5 pixel sensor for an X-ray application. The current issues and future prospect are also discussed. © 2014 IOP Publishing Ltd and Sissa Medialab srl.
-
19aSB-6 SOI技術を用いたX線天文用検出器XRPIXの電荷種集効率の調査(19aSB X線・γ線,宇宙線・宇宙物理領域)
松村 英晃, 中島 真也, 香村 芳樹, 初井 宇記, 亀島 敬, 尾崎 隆吉, 武井 大, 和賀井 達也, 鶴 剛, 田中 孝明, 武田 彩希, 新井 康夫, 森 浩二, 西岡 祐介, 竹中 亮太, 幸村 孝由
日本物理学会講演概要集 69 ( 0 ) 2014年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:一般社団法人 日本物理学会
-
Monolithic pixel detectors fabricated with single and double SOI wafers
Miyoshi T., Arai Y., Fujita Y., Hara K., Honda S., Ikegami Y., Ikemoto Y., Mitsui S., Takeda A., Tauchi K., Tsuboyama T., Unno Y.
Proceedings of Science 2014年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of Science
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. Monolithic pixel detectors have been fabricated with single and double SOI wafers using SOI technology for a next-generation radiation sensor. A single SOI sensor consists of a thin SOI layer as SOI-CMOS circuit, a thick silicon substrate as a sensor, and a buried oxide layer as an insulator between two silicon layers. A double SOI sensor has another thin SOI layer to prevent unwanted effects such as the back-gate effect, the sensor - circuit crosstalk and total ionization dose effect. In 2013, the integration type pixel sensor, INTPIXh2, has been fabricated for the evaluation of single and double SOI sensors. The document describes comparison test results in single and double SOI sensors by measuring the leakage current and X-ray spectra. X-ray spectra in double SOI sensors were obtained for the first time. The problem and future prospect are discussed.
-
Development and performance of kyoto's x-ray astronomical SOI pixel (SOIPIX) sensor
Tsuru T., Matsumura H., Takeda A., Tanaka T., Nakashima S., Arai Y., Mori K., Takenaka R., Nishioka Y., Kohmura T., Hatsui T., Kameshima T., Ozaki K., Kohmura Y., Wagai T., Takei D., Kawahito S., Kagawa K., Yasutomi K., Kamehama H., Shrestha S.
Proceedings of SPIE - The International Society for Optical Engineering 9144 2014年
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of SPIE - The International Society for Optical Engineering
© 2014 SPIE. We have been developing monolithic active pixel sensors, known as Kyoto's X-ray SOIPIXs, based on the CMOS SOI (silicon-on-insulator) technology for next-generation X-ray astronomy satellites. The event trigger output function implemented in each pixel offers microsecond time resolution and enables reduction of the non-X-ray background that dominates the high X-ray energy band above 5-10 keV. A fully depleted SOI with a thick depletion layer and back illumination offers wide band coverage of 0.3-40 keV. Here, we report recent progress in the X-ray SOIPIX development. In this study, we achieved an energy resolution of 300 eV (FWHM) at 6 keV and a read-out noise of 33 e- (rms) in the frame readout mode, which allows us to clearly resolve Mn-K? and K?. Moreover, we produced a fully depleted layer with a thickness of 500 ?m. The event-driven readout mode has already been successfully demonstrated.
DOI: 10.1117/12.2057158
-
Development and evaluation of an event-driven SOI pixel detector for X-ray astronomy 査読あり
Takeda A., Tsuru T., Tanaka T., Matsumura H., Arai Y., Mori K., Nishioka Y., Takenaka R., Kohmura T., Nakashima S., Kawahito S., Kagawa K., Yasutomi K., Kamehama H., Shrestha S.
Proceedings of Science 0 2014年
担当区分:筆頭著者 記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of Science
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. We have been developing a monolithic active pixel sensor with silicon-on-insulator technology for use in X-ray astronomical satellite missions. Our aim is to replace the X-ray charge-coupled device - which is the standard detector in the field - with a device that exhibits a high-coincidence time resolution (i.e., ∼1 μs), superior hit-position readout time (i.e., ∼10 μs), and wider bandpass (i.e., 0.3-40 keV), in addition to having comparable performance in imaging spectroscopy. To realize this detector, we have developed prototype detectors called the "XRPIX" series. XRPIX contains a comparator circuit in each pixel to detect an X-ray photon, and it offers an intra-pixel hit trigger (timing) and two-dimensional hit-pattern (position) outputs. Therefore, XRPIX is capable of direct access to selected pixels to read out the signal amplitude. X-ray signal readout by this function is called an "event-driven readout." In our previous study, we successfully demonstrated the X-ray spectra acquisition by the event-driven readout. However, there were some problems in the circuit operation. Recently, these investigations progressed because of many evaluation tests. In this paper, we describe the development and the evaluation of the event-driven readout by XRPIX.
-
Monolithic pixel detectors with 0.2 μm FD-SOI pixel process technology
Miyoshi T., Arai Y., Chiba T., Fujita Y., Hara K., Honda S., Igarashi Y., Ikegami Y., Ikemoto Y., Kohriki T., Ohno M., Ono Y., Shinoda N., Takeda A., Tauchi K., Tsuboyama T., Tadokoro H., Unno Y., Yanagihara M.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 732 530 - 534 2013年7月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Truly monolithic pixel detectors were fabricated with 0.2μm SOI pixel process technology by collaborating with LAPIS Semiconductor Co., Ltd. for particle tracking experiment, X-ray imaging and medical applications. CMOS circuits were fabricated on a thin SOI layer and connected to diodes formed in the silicon handle wafer through the buried oxide layer. We can choose the handle wafer and therefore high-resistivity silicon is also available. Double SOI (D-SOI) wafers fabricated from Czochralski (CZ)-SOI wafers were newly obtained and successfully processed in 2012. The top SOI layers are used as electric circuits and the middle SOI layers used as a shield layer against the back-gate effect and cross-talk between sensors and CMOS circuits, and as an electrode to compensate for the total ionizing dose (TID) effect. In 2012, we developed two SOI detectors, INTPIX5 and INTPIX3g. A spatial resolution study was done with INTPIX5 and it showed excellent performance. The TID effect study with D-SOI INTPIX3g detectors was done and we confirmed improvement of TID tolerance in D-SOI sensors. © 2013 Elsevier B.V.
-
Nakashima S., Gando Ryu S., Tanaka T., Go Tsuru T., Takeda A., Arai Y., Imamura T., Ohmoto T., Iwata A.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 731 74 - 78 2013年5月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
We have been developing active pixel sensors based on silicon-on-insulator technology for future X-ray astronomy missions. Recently we fabricated the new prototype named "XRPIX2", and investigated its spectroscopic performance. For comparison and evaluation of different chip designs, XRPIX2 consists of 3 pixel types: Small Pixel, Large Pixel 1, and Large Pixel 2. In Small Pixel, we found that the gains of the 68% pixels are within 1.4% of the mean value, and the energy resolution is 656 eV (FWHM) for 8 keV X-rays, which is the best spectroscopic performance in our development. The pixel pitch of Large Pixel 1 and Large Pixel 2 is twice as large as that of Small Pixel. Charge sharing events are successfully reduced for Large Pixel 1. Moreover Large Pixel 2 has multiple nodes for charge collection in a pixel. We confirmed that the multi-nodes structure is effective to increase charge collection efficiency. © 2013 Elsevier B.V. All rights reserved.
-
Takeda A., Arai Y., Tsuru T., Tanaka T., Nakashima S., Matsumura H., Imamura T., Ohmoto T., Iwata A.
IEEE Nuclear Science Symposium Conference Record 2013年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
We have been developing a monolithic active pixel sensor with the silicon-on-insulator (SOI) CMOS technology for use in future X-ray astronomical satellite mission. Our objective is to replace the X-ray Charge Coupled Device (CCD), which is the standard detector in the field, by offering high coincidence time resolution (∼ 50 ns), superior hit-position readout time (∼ 10 μs), and wider bandpass (0.5 - 40 keV) in addition to having comparable performances in imaging spectroscopy. In order to realize this detector, we have developed prototype detectors, called 'XRPIX' series. XRPIX contains comparator circuit in each pixel to detect an X-ray photon injection; it offers intra-pixel hit trigger (timing) and two-dimensional hit-pattern (position) outputs. Therefore, XRPIX is capable of direct access to selected pixels to read out the signal amplitude. In our previous study, we evaluated its basic performance and obtained the X-ray spectra by this system. The next step is improvement in spectroscopic performance. Then, we designed a new prototype, called 'XRPIX3', which has charge sensitive amplifier (CSA) in each pixel. The pixel circuit with CSA works good. It is 3.4 times higher gain as compared with normal pixel circuit. Furthermore, XRPIX3 resolved Mn-Kα and Mn-Kβ successfully for the first time in our series. The readout noise is 33 e- rms and the energy resolution is about 300 eV FWHM at 5.9 keV. In this paper, we report on the design and test results of this new device. © 2013 IEEE.
-
Evaluation of a SOI pixel sensor with thick depletion layer for future X-ray astronomical missions
Nakashima S., Ryu S., Tsuru T., Takeda A., Arai Y., Miyoshi T., Ichimiya R., Ikemoto Y., Imamura T., Ohmoto T., Iwata A.
AIP Conference Proceedings 1427 259 - 260 2012年5月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:AIP Conference Proceedings
We report on the evaluation test of our novel pixel sensor named "XRPIX1-FZ" which is developed for the future X-ray astronomy mission. The mean gain of XRPIX1-FZ is 3.3 μV/e. and the dispersion of the gain among the pixels is 1 in the standard deviation. We confirmed the energy resolution of 260 eV in FWHM at 8 keV. We achieved the full depletion (250 μm) at 30 V back bias voltage. © 2012 American Institute of Physics.
DOI: 10.1063/1.3696193
-
Nakashima S., Ryu S., Tsuru T., Takeda A., Arai Y., Miyoshi T., Ichimiya R., Ikemoto Y., Imamura T., Ohmoto T., Iwata A.
Physics Procedia 37 1373 - 1380 2012年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Physics Procedia
© 2012 Published by Elsevier B.V. We have been developing an active pixel sensor for X-ray astronomy. In this paper, we report on the design and the characterizationof the recently-developed device named XRPIX1-FZ.We applied the high-resistivitySiwafer(∼7 kΩ cm) to the sensor layer for a thick depletion layer. The chemical-mechanical polishing, which we applied to smooth the rough backside of the Si wafer, successfully reduced the dark current. We used the single-pixel readout mode and achievedthe energy resolution of 260eVinFWHMat8keV.Moreover, we developed the 3 × 3pixel readout mode for the evaluation of split events and confirmed the full depletion of 250 μm thick at thereverse-biasvoltageof30 V.
-
Recent Progress of Pixel Detector R&D based on SOI Technology 査読あり
Miyoshi T., Arai Y., Fujita Y., Hara K., Ichimiya R., Ikegami Y., Ikemoto Y., Kasai H., Katsurayama H., Kohriki T., Okihara M., Ono Y., Onuki Y., Shinsho K., Takeda A., Tauchi K., Tsuboyama T., Unno Y.
Physics Procedia 37 1039 - 1045 2012年
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Physics Procedia
© 2012 Published by Elsevier B.V. We are developing truly monolithic pixel detectors with a 0.2 μm silicon-on-insulator (SOI) CMOS technology, which is intended to be utilized in various research fields, such as high-energy physics, X-ray material analysis, astrophysics and medical sciences. In the development project, KEK has organized several Multi Project Wafer (MPW) runs and the process has been incrementally improved. Czochralski (CZ-) and Float-Zone (FZ-) silicon has been used as a starting material for the detector fabrication. Using FZ-SOI wafers, the detectors worked at full depletion below the breakdown voltage. The up-to-date integration-type pixel detector with 14 μm pixel size has excellent spatial resolution.
-
Ryu S., Tsuru T., Nakashima S., Takeda A., Arai Y., Miyoshi T., Ichimiya R., Ikemoto Y., Matsumoto H., Imamura T., Ohmoto T., Iwata A.
IEEE Transactions on Nuclear Science 58 ( 5 PART 2 ) 2528 - 2536 2011年10月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Transactions on Nuclear Science
We have been developing a monolithic active pixel sensor with the 0.2 μm Silicon-On-Insulator (SOI) CMOS technology, called SOIPIX, for the wide-band X-ray imaging spectroscopy on future astronomical satellites. SOIPIX includes a thin CMOS-readout-array layer and a thick high-resistivity Si-sensor layer stacked vertically on a single chip. This arrangement allows for fast and intelligent readout circuitries on-chip, providing advantages over the charge-coupled device (CCD). We have designed and built a new SOIPIX prototype XRPIX1 for X-ray detection. XRPIX1 implements a correlated double sampling (CDS) readout circuit in each pixel to suppress the reset noise. We obtained an energy resolution of full width at half maximum of 1.2 keV (5.4%) at 22 keV with a chip having a 147 μm sensor depletion at a back bias of 100 V cooled to-50°C. Moreover, XRPIX1 offers intra-pixel hit trigger (timing) and two-dimensional hit-pattern (position) outputs. We also confirmed the trigger capability by irradiating a single pixel with laser light. © 2011 IEEE.
-
Development of SOI pixel process technology 査読あり
Arai Y., Miyoshi T., Unno Y., Tsuboyama T., Terada S., Ikegami Y., Ichimiya R., Kohriki T., Tauchi K., Ikemoto Y., Fujita Y., Uchida T., Hara K., Miyake H., Kochiyama M., Sega T., Hanagaki K., Hirose M., Uchida J., Onuki Y., Horii Y., Yamamoto H., Tsuru T., Matsumoto H., Ryu S., Takashima R., Takeda A., Ikeda H., Kobayashi D., Wada T., Nagata H., Hatsui T., Kudo T., Taketani A., Kameshima T., Hirono T., Yabashi M., Furukawa Y., Battaglia M., Denes P., Vu C., Contarato D., Giubilato P., Kim T., Ohno M., Fukuda K., Kurachi I., Okihara M., Kuriyama N., Motoyoshi M.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 636 ( 1 SUPPL. ) 2011年4月
記述言語:英語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
A silicon-on-insulator (SOI) process for pixelated radiation detectors is developed. It is based on a 0.2 μm CMOS fully depleted (FD-)SOI technology. The SOI wafer is composed of a thick, high-resistivity substrate for the sensing part and a thin Si layer for CMOS circuits. Two types of pixel detectors, one integration-type and the other counting-type, are developed and tested. We confirmed good sensitivity for light, charged particles and X-rays for these detectors. For further improvement on the performance of the pixel detector, we have introduced a new process technique called buried p-well (BPW) to suppress back gate effect. We are also developing vertical (3D) integration technology to achieve much higher density. © 2010 Elsevier B.V.
-
Design and development of trigger-driven readout with X-ray SOI pixel sensor
Ryu S.G., Takeda A., Nakashima S., Tsuru T.G., Ikemoto Y., Arai Y., Imamura T., Ohmoto T., Iwata A.
IEEE Nuclear Science Symposium Conference Record 1197 - 1200 2011年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
We have been developing a monolithic active pixel sensor with the Silicon-On-Insulator (SOI) CMOS technology, called SOIPIX, for future X-ray astronomical satellite missions. The goal of SOIPIX is to replace the X-ray CCD, which is the standard detector in the field, by offering superior time resolution (∼10 μs) and wider bandpass (0.5 keV - 40 keV) in addition to having comparable performances in imaging spectroscopy. In the previous work, we built a SOIPIX prototype, XRPIX1, and confirmed the basic X-ray performance of imaging spectroscopy in a mode reading out the whole area (all pixels). The next step is to realize a high-speed and intelligent readout for X-ray detection. XRPIX1 contains trigger circuit in each pixel to detect an X-ray photon and is capable of direct access to the local pixels to read out the signal amplitude. We report on the design and development of a trigger-driven readout system with XRPIX1. We present the first resolved X-ray spectra of Cu+Mo and Am-241 obtained in the trigger-driven mode. © 2011 IEEE.
-
Onuki Y., Katsurayama H., Ono Y., Yamamoto H., Arai Y., Fujita Y., Ichimiya R., Ikegami Y., Ikemoto Y., Kohriki T., Miyoshi T., Tauchi K., Terada S., Tsuboyama T., Unno Y., Uchida T., Hara K., Shinsho K., Takeda A., Hanagaki K., Tsuru T., Ryu S., Nakashima S., Matsumoto H., Takashima R., Ikeda H., Kobayashi D., Wada T., Hatsui T., Kudo T., Kobayashi K., Kirihara Y., Ono S., Omodani M., Kameshima T., Nagatomo Y., Kasai H., Kuriyama N., Miura N., Okihara M.
Proceedings of Science 137 2011年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of Science
© Copyright owned by the author(s). The novel particle and radiation detector using a Silicon On Insulator (SOI) technology has been developing by the SOI collaboration since 2005. The SOI technology can be applied to realize an ideal monolithic detector which consists of electrical insulator sandwiched low resistivity thin wafer for electronics and high resistivity thick wafer for sensor without bump bonding. The multilateral developments for both fundamental properties and dedicated application are progressing simultaneously. The one of the most important break through we had achieved is a buried p-well (BPW) technology. This technology help to lead recent various applications for specific scientific interest such as X-ray diffraction analysis, X-ray astronomy and high energy particle detector. We report recent studies of process based improvements, radiation tolerance and high energy particle tracking.
-
Performance study of monolithic pixel detectors fabricated with FD-SOI technology
Miyoshi T., Arai Y., Ichimiya R., Ikemoto Y., Takeda A.
IEEE Nuclear Science Symposium Conference Record 1702 - 1707 2011年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
We are developing monolithic pixel detectors with a 0.2 μm CMOS, fully-depleted silicon-on-insulator (SOI) technology. The substrate is high-resistivity silicon and works as a radiation sensor having p-n junctions. The SOI layer is a 40 nm thick silicon, where readout electronics is implemented. There is a buried oxide (BOX) layer between these silicon layers. We have already done several Multi Project Wafer (MPW) runs by gathering many pixel designs into a photo mask set, and as the results, several types of integration type pixel detectors (INTPIX) were fabricated. In this document, the design concept and performance in some of INTPIX detectors are described. © 2011 IEEE.
-
Nakashima S., Ryu S.G., Tsuru T.G., Arai Y., Takeda A., Nakajima H., Tsunemi H., Doty J.P., Imamura T., Ohmoto T., Maeda T., Iwata A.
IEEE Nuclear Science Symposium Conference Record 1201 - 1203 2011年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
We have been developing a novel X-ray astronomy detector combined with a CMOS readout circuit on a monolithic chip using the SOI CMOS technology. As a part of the development, we have fabricated a prototype of an analog-to-digital converter (ADC) component aiming for building it into the detector itself. We used the OKI 0.2 μm CMOS fully depleted Silicon-On-Insulator process. The prototype ADC consists of a pre-amplifier and two delta-sigma (ΔΣ) modulators. The two modulators process a series of analog input signal alternately to improve the readout speed (∼100 kHz), and output the digital bit-stream signal. An external Field Programmable Gate Array works as a decimation filter and converts the bit-stream signal into a 12-bit digital signal. We evaluated the prototype ADC and obtained the first results as follows: the power consumption of 40 mW, the equivalent input noise of ∼80 μV rms, and the integral non-linearity of less than 0.8%. © 2011 IEEE.
-
Development of FD-SOI monolithic pixel devices for high-energy charged particle detection
Hara K., Shinsho K., Ishibashi T., Arai Y., Miyoshi T., Ikemoto Y., Ichimiya R., Tsuboyama T., Kohriki T., Yasu Y., Onuki Y., Ono Y., Katsurayama H., Takeda A., Hanagaki K.
IEEE Nuclear Science Symposium Conference Record 1045 - 1050 2011年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
Monolithic pixel devices fabricated with a siliconon-Insulator (SOI) technology are excellent candidates to realize particle detectors of fast response and least material yet simple in fabrication. In our SOI pixel devices the sensitive part is the "handle" wafer, to which we examined high resistive FZ wafers of both p- and n-types together with CZ wafer of n-type. Full depletion of the FZ wafers is easily achievable for typical thicknesses of 260 to 500 μm. We thinned these devices to 100 to 50 μm. The response was evaluated with infrared and red lasers, and in a high energy beam. Irradiation to 60Co γ was carried out to verify the radiation tolerance of the devices. © 2011 IEEE.
-
Development of X-ray imaging spectroscopy sensor with SOI CMOS technology
Ryu S., Tsuru T., Nakashima S., Arai Y., Takeda A., Miyoshi T., Ichimiya R., Ikemoto Y., Takashima R., Imamura T., Ohmoto T., Iwata A.
IEEE Nuclear Science Symposium Conference Record 43 - 48 2010年12月
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:IEEE Nuclear Science Symposium Conference Record
We have been developing a monolithic active pixel sensor with the 0.2 m Silicon-On-Insulator (SOI) CMOS technology, i.e. SOIPIX, for the X-ray imaging spectroscopy on future astronomical satellites. SOIPIX includes a thin CMOS readout layer and a thick high-resistivity Si-sensor layer vertically on a single chip, which would provide advantages in capabilities of direct and flexible readout circuitries over charge-coupled device (CCD). We have built INTPIX2/3 (2008/2009) and XRPIX1(2010). We successfully confirmed the capability of X-ray imaging and spectroscopy in a photon-counting mode by irradiating INTPIX2/3 with monochromatic X-rays. To reduce the readout noise, we designed and built XRPIX1, which has a correlated double sampling (CDS) readout circuit in each pixel to suppress the reset noise. We obtained an energy resolution of FWHM 1.5 keV(7%)@22 keV with XRPIX1 cooled at 50 degree. Moreover, XRPIX1 offers intra-pixel hit trigger and one-dimensional hit-pattern outputs. We also confirmed the trigger capability by irradiating a single pixel of XRPIX1 with laser light. © 2010 IEEE.
-
Development of INTPIX and CNTPIX Silicon-On-Insulator monolithic pixel devices
Hara K., Kochiyama M., Koike K., Sega T., Shinsho K., Arai Y., Fujita Y., Ichimiya R., Ikegami Y., Ikemoto Y., Kohriki T., Miyoshi T., Tauchi K., Terada S., Tsuboyma T., Unno Y., Horii Y., Onuki Y., Nio D., Takeda A., Hanagaki K., Uchida J., Tsuru T., Ryu S., Kurachi I., Kasai H., Kuriyama N., Miura N., Okihara M., Motoyoshi M.
Proceedings of Science 113 2010年
記述言語:日本語 掲載種別:研究論文(学術雑誌) 出版者・発行元:Proceedings of Science
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. We are developing monolithic pixel detectors utilizing a silicon-on-insulator (SOI) process commercially provided by OKI Semiconductor. Two main pixel sensors, INTPIX and CNTPIX, are being designed as signal integration and counting type devices, respectively. We describe the fabrication results including a buried p-well (BPW) technology recently adopted. The BPW is a breakthrough suppressing the back-gate effect. The radiation resistance of the BPW was also investigated. The ultimate solution to the back-gate effect suppression is stacking of two SOI wafers. We are investigating a 3D process. We also describe the successful results of thinning the wafer to 100μm.